Dating from the Adams and Eves Threads

How much documented evidence do you need?I don't know how you can even say that and keep a straight face.It is extremely well known and well documented that the very common N14 atom will readily accept a neutron from any neutron producing radioactive source to become C14.It can actually become N15 too but the probability of the pathway is much smaller.
The Thermal Cross Section of the reaction (N14 + Neutron = C14) has been repeatedly measured and calculated to be 1.83. This is one of the highest probability reactions known to nuclear science.
The other path (N14 + Neutron = N15) is 0.075 so you can see which way it is most likely to go.(It is even possible, though very improbable, for C12 to accept a neutron to become C13 which in turn can accept another neutron to become C14.)If you need documentation then take a look at this previously classified document. Page 15 shows a study of in vitro formation of C14 in living tissue due to exposure to slow neutrons during an incident at Los Alamos laboratories.I work in a nuclear research reactor every day of my life. We need to know precisely which isotopes can be irradiated to create other isotopes. The pathways are very well understood and documented.If you have N14 isotopes and any radioactive source that emits neutrons (such as naturally occuring U235), you will make C14 isotopes. Period
This is not a hypothesis.
This is not an unsubstantiated belief.This is a fact with so much evidence that it would take you several lifetimes to even read it all. It has been directly observed and measured in just about every reactor in the world for more than 50 years.Since the crust of the Earth contains large quantities of Uranium (particularly in granite and other igneous rock), of which a small percentage is U235, It would be almost impossible for some of the N14 isotopes in most everything that comes into contact with this igneous rock to not be somewhat enriched with C14.This message has been edited by PurpleYouko, 12-19-2005 01:36 PM

In this specific case, the neutron donator was a radiation leak of some undisclosed nature that effected workers.Yes the surroundings do affect absorption of neutrons. Water is one of the better moderators which is why it is used in reactor cores. It serves to slow a fast neutron, emitted from a decaying Uranium nucleus, so that it can be absorbed more easily. Often it adds to 1H (Hydrogen) to make 2H (deuterium) or even 3H (Tritium) and makes "heavy water", however it is just as likely to combine with any Nitrogen 14 that is present to make Carbon 14.The rest of your post is a pretty good description of some of the known radioactive decay processes but I don't see what point you are trying to make with it, other than to bolster the validity of carbon dating techniques.

You can't compress water!
ALL water is 100% uncompressible.

Hi Iano. Same to you.
BTW. Christmas works just fine for me. Being an Atheist doesn't mean I can't put up a bunch of lights and a tree and join in the spirit of the thing. I actually find it a little annoying when people say "Happy Holidays" due to an over active political correctness gland.Anyway, Coragyps pretty much nailed it as far as water compressibility goes. It will compress very slightly but it would take an enormous amount of pressure to significantly affect it. in the upper 1000 feet or so of depth it is barely mesurable so in terms of lake Suigetsu (in the context mentioned by the Golfer for some reason that I have yet to figure out) it is completely irrelevent.PS Bit unusual to see you playing over here in the science threads.

Golfer.You do realise that these bacteria that are eating Kerogen, are believed to be aerobic right?

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Petsch thinks perhaps that the bacteria need oxygen in order to consume the kerogen. While the shale exposed to the atmosphere had less kerogen, the deeper rock had limited oxygen exposure and thus less bacterial activity.

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"Consumption of the shale most likely does depend on exposure environment," says Petsch. "In the deep subsurface, oxygen could not penetrate from air into the rock. Our work seems to indicate that availability of oxygen plays some role in how kerogen is consumed. So at depth, microbial activity should be very limited."

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They can only eat it when it is exposed to air or to well oxygenated water. While the shale is burried under more than a few inches, they can't do anything to it.Same applies with lake varves. Bacterial action will only be possible in the top layers. This is true whether they are aerobic or anaerobic. Even anaerobic bacteria need to be able to utilize some gasses like Nitrogen or SulferThis message has been edited by PurpleYouko, 12-21-2005 04:53 PM

Hey tsjust for your information, Iano wasn't being serious when he wrote that.He was just ragging me for fun.He and I have a kind of friendly banter going on when we aren't actively arguing with each other.

I'm sorry but this is utterly ridiculous.
I make my living by accurately measuring the neutron flux leaving atoms. That is how a reactor works.
We use the neutron flux to create new isotopes all the time. We combine these radioactive isotopes with organic ligands to make drugs to combat cancer.
My job is most often to measure the exact isotopic concentrations of samples which we put into the reactor, both before and after irradiation by thermal neutrons, without which neuclear fission would not be possible. I measure these with a bank of highly accurate mass spectrometers.No matter what you think, you are quite obviously not a nuclear phycisist. neutrons can and do leave atomic nuclei. They do so in a highly predictable (statistically) manner. One of my other jobs is to develop computer software to accurately predict the outcome of these irradiations. When the predictions accurately mirror the actual results, we can be pretty darn sure that the reactions are going exactly as planned.As I told you before, there is no gray area here. We know exactly what is going on with nuclear decay reactions. It has been extremely well measured and documented. You can bury your head in the sand, stick your fingers in your ears and pretend you don't hear what we are all telling you but that doesn't change the reality of the situation.
Neutrons do leave nuclei of some atoms!
Nitrogen 14 does accept a neutron then emit a proton and a gamma ray to leave Carbon 14. We have measured it, simulated it and artificially recreated it until we are blue in the face. IT HAPPENS Deal!!!

Hey Golfer.Edges link may have said that

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First, any practical portable neutron source will not provide you with thermal neutrons

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but did you read the whole article?
The problem with mobile sources is that they produce fast neutrons in the MeV range which need to be moderated or reduced to the eV range before they can be readily captured by an atomic neucleus.This passage was taken from Edge's link.

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To obtain thermal energies (i.e., in the eV range), you will have to moderate these neutrons through collision interactions with hydrogenous material”such as water, heavy water, paraffin, high-density polyethylene, etc.

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Note the mention of water as a suitable moderator. After all we are talking about radioactive sources in contact with an underground aquifer here. Once the fast neutron travels through a few feet of water, it is good and ready to be absorbed by any suitable neucleus.As for the source of the neutron, one possible source is also mentioned in Edge's link. Alpha particles (from Uranium perhaps)colliding with something such as berrylium and releasing a neutron. Seems kind of unlikely admittedly but there is a much more viable source of neutrons.Spontaneous fission!All heavy neuclei (mass 100 and greater) are prone to this to some degree although it is most common in neuclei greater than 230 in mass. Things like Thorium, Uranium and Plutonium are quite prone to this. We use this to initialize a nuclear chain reaction in a bomb or a reactor. There has to be a source of neutrons before the mass can go critical.In naturally occuring heavy elements, spontaneous fission can produce quite significant numbers of fast neutrons. This link provides a few details of this.

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Uranium-238, for example, yields almost 60 neutrons per hour per gram.

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Since Uranium is such a common element in the earth's crust (several 10s of parts per million typically), is it so hard to believe that underground water could come into contact with it?
Given the sensitivity of modern detection equipment, it wouldn't take very many neutron-N14 collisions to make enough C14 to screw up the radiometric dating to give artificially young ages.
It would seem to me to be almost impossible for this NOT to happen in underground water. All the necessary parts are there. Neutron source, Moderator and dissolved Nitrogen. Here is another link that describes spontaneous fission, just in case you want to read up on it some more.There is no doubt. The thermal neutrons ARE there.

Golfer Take a look at this useful link
Follow the chain of decay products from Uranium 235.It isn't as simple as just alpha decay. You also have to look at the decay products like Actinium, Thorium and Radon.Alpha decay, as you say consists of two neutrons and two protons being ejected from the nucleus of the parent. This "chunk" quickly grabs a couple of electrons to become Helium 4.
Then there is Beta decay which consists of a high energy electron.
There is Gamma decay which consists of the emission of one or more high energy gama rays at very specific frequencies as the isotope drops from a meta-stable state to a more stable one.
Some isotopes even decay by capturing an electron. An example of this is Radon 211 which can decay from Francium 211 by electron capture.Then again there is Spontaneous Fission in which a nucleous simply splits into smaller parts, releasing alphas, betas, gammas and neutrons in varying numbers.The extremely motile Radon is also able to undergo spontaneous fission and the stuff is everywhere, even in my basement.

Golfer. I think you may have got hold of the wrong idea about decay. Neutrons and protons do not decay into helium.
Large unstable atomic nuclei decay by emiting a chunk of material which is comprized of 2 protons and 2 neutrons. This is an alpha particle or a Helium nucleus if you prefer. neutrons and protons don't decay to make it. It is already made when it leaves the larger nucleus.
There is no cold fussion here.And what is this about 2.65 years half lives?
Is this just because the link mentioned Californium 252?That just happems to be one of the longer lived, artificially created isotopes that are comercially available. Most radioactive isotopes have much longer half lives. that just means that they decay far more infrequently and are a lot less use as a portable source of neutrons. Who wants to wait a few billion years for a given atom to decay when you can get Ca252 which will do it in two and a half years? Yes, large mass atoms do decay in steps of 4 mass units at a time by Alpha decay. No protons and neutrons don't combine after emission. They do it during the emission process. Neutrons and protons in the nucleus simply rearrange to more stable formations and this results in two distinct and seperate nuclei which then fly apart. There is no fussion of any sort going on here. Umm? It is decaying neutrons without protons. Fission has nothing to do with alpha decay. It doesn't involve protons at all.
Here is a neat little diagram to demonstrate how fission works.
it shows the fission of an atom of U235. Note that the products include Rb90, Cs143 and 3 free high energy neutrons.Fission is usually initiated by the parent atom absorbing a thermal neutron, thus increasing its instability, but as I showed you earlier, spontaineous fission does happen. I have plenty more links if you want them.I am not going to bother responding to the rest of the post since
1) It has little or nothing to do with my point of N14 neutron capture to make C14 in underground water sources.
2) It appears to devolve into meaningless and disconnected rambling.